This invention is an outgrowth of personal size, home use hot water vacuum extraction machines incorporating within a dump bucket employed in both wet and dry vacuum systems of a hydro air filter having an end of the hydro air filter immersed in water within the dump bucket. Such systems cause dirty air under vacuum pressure returning to the dump bucket from a vacuum cleaner to a vacuum head mix with the water accumulating within the bucket, or provided to the same. The dirt particles separate from the air stream and are retained by the water. The dirt-free air stream is released to a space defined by the top of the bucket and an overlying dome cover and then passes downwardly through a riser tube under suction pressure from a vacuum pump coupled to the lower end of the riser tube. Air, thus escapes from the dump bucket and after passage through the suction pump, is permitted to pass laterally through openings within the wet vacuum extreme casing to which the dump bucket is removably mounted.
The hydro air filter or aqua filter is an improvement in a developing field of small size home vacuum extraction machines exemplified by, U.S. Pat. No. 4,078,908, issued Mar. 14, 1978 to R. Eugene Blackman and entitled "DUMP BUCKET FOR A WET-DRY VACUUM SYSTEM HAVING IMPROVED LIQUID FLOW CHARACTERISTICS"; U.S. Pat. No. 4,083,705, issued Apr. 11, 1978 to Carl Parise et al. and entitled "DUMP BUCKET FOR A WET/DRY VACUUM SYSTEM"; and U.S. Pat. No. 4,145,198, issued Mar. 20, 1979 to Thomas M. Laule and entitled "SINGLE TUBE HYDRO AIR FILTER WITH DIVIDING WALL".
Such machines, whether used as a dry vacuum cleaner or a wet vacuum cleaner, eliminate a problem in the dry vacuum cleaner art which has existed for many, many years. Typically, a dry vacuum cleaner employs a porous bag, within which air is drawn by vacuum pressure from a electric motor driven vacuum pump, which sucks into the bag, dust particles from a rug or other surface being cleaned through a vacuum head. The largest of the dust and dirt particles are retained internally of the bag. The very nature of the dry vacuum cleaner porous bag operation requires that the air stream entering the bag escape through the pores of the bag. Any-dust particles which are sized less than the size of the pores obviously escape through those pores, returning to the room being cleaned an atmosphere of small dust particles floating around after cleaning has been terminated. Such vacuum cleaning processes are inefficient, since they disturb the dirt particles which are dormant within the rug and while extracting and separating the larger dirt particles and create a room atmosphere of millions of small dust particles. Such particles may be easily seen in the sunlight streaming through a window within a room subject to conventional dry vacuum cleaning.
Some of the hot vacuum extraction machines, as set forth in the above identified patents, have within the machine casing and disposed in the path of the return air passing downwardly through the riser duct opening to the suction side of the vacuum pump, a porous structure filter such as a thin porous pad which functions primarily to remove coalesced water particles traveling with the air stream. To some degree, any particles escaping from an area above the water level within the dump tank are carried downwardly through the riser tube and are captured within the pores of the filter pad.
In the ensuing years, the public has become more and more conscious of air contamination. Many Americans who are smokers have given up the habit. Non-smokers are aware of secondary smoke inhalation. Indeed, workplaces today have been rendered cigarette smoke free to address such concerns. Restaurants have either become smoker free, or have segregated non-smoking sections for their patrons. There is therefore a need for removing all particles, even of submicron size to render the home, office areas, restaurants or the like 100% particle free.
It is therefore a primary object of the present invention to provide an improved home use, lightweight hot water vacuum extraction machine which can effectively clean rugs, floors, drapes, upholstery and the like, while rendering the atmosphere of the cleaning area dust free and allergy free by trapping all air contaminants and allergies, down to submicron size.
It is a further object of this invention to provide an improved hot water vacuum extraction machine which employs alternatively a urethane foam filter pad for trapping larger sized contaminant particles in excess of submicron size, or an electrostatic allergy filter pad which is capable of trapping all air contaminants and allergants down to submicron size.